Quick-action release mechanism for air-brakes.



S. G. NEAL. QUICK ACTION RELEASE MECHANISM FOR Am BRAKES. APPLICATION FILED NOV. 2, 1914. 1,12 822, Patented Feb. 16, 1915.

Z SHEETS- SHEET 1.

27 11 a 2W a I l .l

13 35 J4 IESSES: l/Vl/E/VTUH I ,4 TOR/VH5 S. G. NEAL.

QUICK ACTION RELEASE MECHANISM FOR AIR BRAKES.

APPLICATION FILED NOV.2,1914.

'1 1 2&62'2, Patented Feb. 16, 1915.

2 SHEETSSHEET 2.

h w I I 10 4% WITNESSES: II-NVENTOR E To Zill whg m i t concern UNITED srrrrus PATENT orribu SPENCER e. or Los endures, cALIrohNney-Assmnon' ref cA rronN xL'vAr-vE AND AIR B COMPANY, or Los ANGEL'ES'; CALIFOR IA, A coom'rrou or CALIFORNIA;

-QUICK-ACTIN RELEASE MECHANISM FOR AIR-BRAKES.

Specification of Letters Patent. Patient a 1L6,

l ":25 h 3 Application filed November 2, 1914. Serial No. 869,773.

,Be it known that I, Srnixoni State of California,- I have invented certain new and useful Improvements in Quick- 'ction Release ratusshown and described in thatpatent the [rain line or train pipe is the source of air supply during service braklng, and the train pipe, or train line, capacity is" in;

creased by providing a r e se rvoir for each braking unit, from which rese voir thetrain pipeisesupplied. locally di'iring serviceepplice-tions of i he'brakes. In the operation of bmking apparatus suchasthatlshown in my said patent, and as shown in my Patent No. 1,078,393, dated November 1. .1. it has beemfound that it requires considerable time tim release thebrakes on a long train by increasing,- the trainpipepressure from the main .I reservoir of the locomotive It is manifestthatshould ,a train be time before the brakes on the rear cars are released the couplings, are likely to be brolgen and the train parted. In verylongtrains the time, required. for: -releasing the brakes on the rear cars is considerable,andyaries to such anextent that it is difficultfor the engiueer to accurately determine vhen it is safe to start histrain, Frequently a tratin will be prematurely started with the result that the couplings andbraking apparatus on the rear ca rsare damaged, it not broken and the train parted. w

It is one of, the main objects of this inven; on to provide means for rapidly increasing train pipe pressure locally, undereach car by placing the auxiliary reservoir in direct communication with the train plpebya slightincrease of'tralnplpe pressure. fly this eans the train pi e .pressurenvy llbe rapi y-increased at eac bralqng unit and the wave of. increased prewilre, will mwe with great rapidity, throughoi lt the train line. ItHis manifest that by producing a rapid increase in train line pressllre at each braking ,unit by discharging the EIIF fIJQI II each auxiliary reservoir into the tram line,

. citizen of the UnitedStates and resident of Losr-Kngeles, county of Los Angeles, and

vide means whereby the quic .132 f ".1 :"7 J1- the nicrease ln train l ne pressure sufficient for the releasing action will almost stantaneous throughout the train line, and this pra'cti'cally. Without regard to the length of the train line glt is also ifia nifest that iii a braking apparatus operatirti'g as described the air taken from the ihain reservoir on the locomotive need only be suflicient to operate the releasing device or valve on the firstcar 'o flthe' ,train, or on the first car equipped with the quick-release apparatus, so that the main reservoir will not be dep lcfiechto any material extent to seciire thequick-releasing action. 7 v

i-fl nother' object of the invention is to provide a yalv device adapted to be placed between the train line augmenting reservoir of my Patent No. 1,082,758 and the train line,

tween the aux liary reservoir-and said inech-' anisin, the braking apparatus as' a Whole then operating precisely as, shown and described in m said Patent No. 1,082,758, or as it- Wasor inally intended and de'si ed to egeiate, wlthout the quick-action re ease mec auisrn. ,e V i jinothe'r ob'ec t of the invention to provi e means or quickly discharging the augmenting reservoir air into the train line and for sloyvly recharging the augmenting reservdir when the train line pressure ,is increased, v The purpose of this is to perriiit tlie traih line pressure to be raised rapidly without the necessity of supplying uiiicient air to quickly recharge the an eniirig reservoir, the traiii line pressure thereby raised rapidly in advance of the increase in pressure in the augmenting reservo'i'. 1 While i have indicated herein that this intention is adapted for use ,with my triple valv'e and braking appartus shown in my Patent No. 1,082,758, it is to be understood that it ma be used, with other forms or brakingapparatus and triple valves, such, for ins nce, as disclosed in my PatentNo. iptseoa In the drawings, Figure 1 is a diagrammatic view of a braking unit showing-the quick-action release mechanism combined with a braking unit Fig. 2 a vertical central sectional view of the quick-action release valve deviceshowing the parts in position for releasin the auxiliary reservoir air into the train line; F 1g. 3 a similar v1ew showing the valve mechanism in positionto admit augmenting reservoir 7 air into the train line, communication between the auxey iliary reservoir and train line being closed;

' Fig. 4 a detail sectional view showing the valves for controlling communication, between the .augmentlng reservoir and train line, with the parts the positionshown in- Fig; '3';"'and Fig. 5 a detail view showing means for feeding air into the auxiliary reservoir through the quick-action release 1,082,758 hereinbeforexreferred to.

. parts constitutewhat I term a braking unit and,-of course, are repeated on each car of the train as described in my said patent.

Interposed in the train line and between the triple valve and the train line' augmenting reservoir is a quick-action release valve mechanism, which as a whole is designated by the reference letter A. This valve mechanism consists of a main body part 6; a

lower section or member 7 and an upper see I tion ormember 8, said sections being secured together by suitable bolts. The main casing or section is formed at its upper end with the large train line chamber 9. Across the upper end of this chamber is secured a main-diaphragm 10, the marginal edges of said diaphragm being clamped between the upper section 8 and a flange on the upper end of the central section 6. The section 8 forms a train line augmenting chamber 11 above the diaphragm 10. In the main'section 6 below the train .line chamber 9 is formed'an auxiliary reservoir chamber 12 coaxial with .the trainline chamber and of considerably smaller diameter. Closing the lower end of-this chamber 12 is a diaphragm 13, said diaphra of course, being considerably smaller in diameter than the main diaphragm 10. The section 7 of the casing forms a train line chamber 14 below the diaphragm 13 equal in diameter to chamber 12,

and said'smaller chamber is-in communication with the large train line chamber 9 through a passage 15. The train line cham- 17. The auxiliary reservoir chamber 12 is connected to the auxiliary reservoirthrough v pipe 18 and the passage 19 in the central section of the valve casing. In this passage 19 .is a self-seating valve 20, said valve permitting air to flow from the auxiliary reser- -voir into :thechamber 12 but seating and preventing air passing from the said chamber 12 into pipe 18.

plunger 26, on the upper endkof which is formed a valve-27, said valve eing within the train line augmenting chainber l1 and above the diaphragm 10. The plunger 26' extends loosely through the central hub 28 of the main diaphragm clamping plates; and the valve 27 is adapted to engage a valve seat formed. at the upper end of said central'hub. The-aperture through said hub is' of such size that when the valve 27 is unseated there will be a free, unobstructed passage of considerable capacity connecting the train line chamber 9 with the augmenting reservoir chamber 11. Diaphragm 10 is free to move independently of the plunger 26, said diaphragm being what may be termed a floating diaphragm or abut ment. F ormed in the valve-carrying plunger 26 and connecting the train line chamber 9 with the augmenting reservoir chamber 11 is a restricted feed port 29, said port affording communication betweensaid chambers when the valve 27 is seated and closed, so that train line airmay feed slowly into the augmenting reservoir. I

- The lower clamping plate of the diaphragm 13 is formed with a central hub 30, said hub extending up into the auxiliary reservoir chamber 12. Connected to the upper end of this hub is a rigid stem 31 formed .integral with the plunger 26, whereby said plunger and diaphragm reciprocate together. The lower clamping plate of said diaphragm 13 is formed with a depending .guiding stem 32 which is suitably guided by the lower section 7 of the valve casing. Threaded through the upper wall of the sec tion 8 of the valve casing is an adjustable stop 33 which limits the vertical movement of the plungen 26.

The operation of the apparatus may be briefly setflfortlfr as follows: When initially charging the apparatus, train pipe. air flows through passage 15 to chamber 9. Diathrough pipe 16 into chamber 14 an'd nieaeaa phragms 13 and 10 will be raised, thereby unseating valve 24 and opening communication between train line chamber 9 and auxiliary reservoir chamber 12 so that said chamber 12 will be charged to equalization with the train line and auxiliarv reservoir.

It will, of course, be understodd that the ized with the train line and auxiliary reservoir. Upon. a reduction of train pipe pres-t sure to secure a service application of the brakes, pressure will be reduced in chambers 1d and 9, and diaphragm 10 will be depressed by the superior pressure in chamber 11 and diaphragm 13 will be depressed by the superior pressure in auxiliary reservoir The downward movement of chamber 12. the diaphragm 13- will seat valve 2-4 and close communication between train line chamber 9 and auxiliary reservoir chamber 12; and the downward movement of the diaphragm-10 will open free communication between the augmenting reservoir chamber 11 and train line chamber 9, thereby supplying the additional amount of air to the train line for effective application of the brakes,

. as described in my aforesaid Patent No.

1,082,758. Upon raising the train pipe pressure for a release of the brakes the increase of pressure in chamber 9 will immediately raise diaphragm 10 sufiiciently to seat valve 27, and thereafter air from chamber 9 will feed slowly through port 29 into chamber 11 until there is an equalization of train line and augmenting reservoir pressures.

When the diaphragm 10 has been raised sufv ficiently to seat valve 27 the upward pressure on said diaphragm tends to move upwardly the plunger 26 to unseat valve 2+. As diaphragm 10 reatly exceeds in area the diaphragm 13, t e pressure on said diaphragm 10 plus the train line pressure on the lower side of diaphragm 13 will cause the diaphragm 13 to move upwardly thereby unseating valve 24 and opening communication between the auxiliary reservoir chamber 12 and the train line chamber 9/ As soon as valve-24 is unseated auxiliary reservoir air will unseat valve 20 and pass to chamber 12 and thence around valve 24 into train pipe chamber 9 and to the train pipe until there isan equalization of pressures in the train line and auxiliary reservoir. This rapid discharge of auxiliary reservoir air into the train line will quickly raise train line pressure locally under each car and there will be a quick e ualization of pressures established between t e train line and auxiliary reservoir and a slow equalization in augmenting reservoir.- In Fig.2the valves are shown 1n POSItIOII PGIImI lJtIIIg a discharge of auxiliary reservolr a r nto the 'train line. If a further service application be desired this may be secured by another reduction in train line pressure and a further quick release may be obtained in the same manner as before descr bed. It is manifest that by again raising train line pressure the valve device will be operated to discharge auxiliary reservoir air into the train line for another equalization of pressures and a quick release of the brakes. As set out iii my aforesaid Patent No. 1,082,? 58, when train line pressure andauxiliary reservoir pressure are equalized the triple valve moves to full release position, and this action takes place without regard to the degree of equalization pressure. It will also be understood that after a release of the brakes a continued increase, in train line pressure by means of main reservoir air will restore the various pressures to normal; In Fig. 3' valves are shown in position to permit augmenting reservoir air to pass into the train line.

If it be desired to dispense with the quickaction release valve mechanism, communication between-the auxiliary reservoir and the auxiliary reservoir chamber 12 may be closed by means of a valve 34. When this valve is closed the quick-action release mechanism has no effect upon the operation of the remaining portion of-the apparatus. The augmenting reservoir is slowly char ed through the port 29 and will be rapifiiy discharged around valve 27 into the train line when the train line is reduced for brake applications. The valve 34: may be placed in any convenient position on the car, the pipe 18 being looped for the purpose. On long trains it may be found-desirable'to close the Valve 34 on the cars at the head end of the train and toopen it on the cars at the rear of the train. in this way all of the functions of the triple valves on the forward end of the train will be under the control of the engineer, while on those cars on which the valves 34 are open the quickrelease action will be secured.

In order that the valve 27 shall normally tend to seat and close. communication between the augmentin reservoir chamber 11 so that a slow raising of train pipe pressure will not be instantly registered on the opposite side of thediaphragm', whichwould be the case if the valve should remain open.

Whenthe valve 24 is seated to close communication between the auxiliary reservoir 12 and the train line chamber 9 the lower end of the feed port 29 ismoved below the upper end of .the bushing 22 so that said feed port isconsiderably restricted. The

purpose of this is to insure the upward formed either around valve 20 or through it, whereby air from the auxiliary reservoir chamber 12 may feed slowly into the auxiliary reservoir should the auxiliary reservoir pressurebe less than the pressure in the .said chamber 12. This feed port is shown,

in Fig. 5 of the drawings.

What I claim is: 1. An air brake apparatus comprising a train line, a triple valve, an auxiliary reser- 85 between the train line and-'theaugmenting voir, a brake cylinder, a train line augmentmg reservoir, and a valve device interposed reservoir and operated by variations in train line pressure to place the auxiliary reservoir in communication with the train line.

2. An air brake apparatus comprising a train line, a brake cylinder, an auxiliary reservoir, a triple valve and a valve device actuated by train line pressure and auxiliary reservolr pressure and connected to the train line and to the auxiliary reservolr and operatlng upon an increase of tram p1pe pressure after a servlce appllcatlon of the brakes to discharge the auxiliary reservoir air into the train line.'

3. An air brake apparatus comprislng a train line, a brake cylinder, an auxiliary reservoir, a triple valve operating to release the brakes upon an increase of train pipe pressure and a valve device actuated by train line pressure and auxiliary reservoir pressure and interposed between the tram line and the auxlllary reservoir and operating .upon an increase of train line pressure after a service application of the brakes to release the auxiliary reservoir pressure into the train line.

4. An air brake apparatus comprising a train line, a brake cylinder, an auxiliary reservoir, a triple valve operating upon a reduction of train pipe pressure to admit air to the brake cylinderand upon an increase of train pipe pressure to release the brakes, a valve device actuated by train' line pressure and auxiliary reservoir pressure and interposed between the train line .and the auxiliary reservoir and operating when train linepressure is increased aftera service application to admit auxiliary reservoir air to the train line.

5.- An air brakeapparatus comprising a train line, a brake cylinder, an auxiliary reservoir, a triple valve, a valve device actuated by train line pressure and auxiliary reservoir pressure and interposed be. tween the train line and the auxiliary reservoir and adapted to operate to place the auxiliary reservoir in communication with the train line when the train line pressure is increased, after a service application of the brakes.

6. An air brake apparatus comprising a train line, a brake cylinder, an auxiliary reservoir, a triple valve, a train line augmenting reservoir and a valve device inter-' train line, brake cylinder, auxiliary reser-- vo1r,tr1ple valve, a train line augmenting reservoir, a valve device interposed between the train line and the augmenting reservoir, a movable abutment therein subject to train line pressure and augmenting reservoir pressure, a second abutment in said devicesub ect to train line pressure and auxiliary reservoir pressure,-a valve actuated by said abutments and operating upon an increase of train pipe pressure after a service application of the brakes to open communication between the auxiliary reservoir and the train line.

8. A quick -'release mechanism for air brakes comprising a casing formed with a train line chamber of large diameter and an auxiliary reservoir chamber below and smaller in diameter than the train line chamber, movable abutments secured across said chambers, a train line chamber below the abutment in the auxiliary reservoir chamber and connected with the larger train line chamber, a-train line augmenting chamber above the movable abutment of the larger train line chamber and valves operated by said movable abutments to control communication between the auxiliary reservoir chamber and the train line chambers and between the train line chambers and the train line augmenting chamber.

9. A quick-release mechanism for air tr ee' the train line chambers and the train line augmenting chamber. I

10. A quick-release brakes comprising a casing formed with a chamber of large capacitv and witha cha n ber of considerably sma er capacity belo'vv and coaxial With the largerchamber, a movable abutment dividin the larger chamber into a train line chamer and a trainlinc augmenting chamber, a .movable a utment dividing the smaller chamber mtq an aux iliary, reservoir chamber and a, tram line chamber, said latter chamberbeing in open communication with the larger train line chamber, and valvesoperated by saic lmo v; able abutments to control commun cation between the aup'ziliary reservoir chamber and the train line chambers; and betvven the train line chambers and the tram augmenting chamber, said valves be ng con- .nected'to and moving with theabutment in the auxiliary reservoir chamber, the abut; m t eie t pr re n the am 1111.8 augmenting chamber being movable independently of said valves.

11. air brake appara'tus comprisinga train line, a triple valve, an auxiliary, reservoir, a brake cylinder, a trainl ne augmenting reseryoir, a valve dev ce interposedbe; tween the train line and the augmenting reservoir and. operated by variations ,in trainline ,.pressure to place the auxil ary reservoir communication with the tram line, and means vfor closing commumeat e between the auxiliary reservoir and the SM valve device. I e I L l2. a'r brake apparatus comprl slnga train line, a brake cylinder an auxihary. res:- ervoir, a triple valve operating upon reduction qt t rainpipe pressm'eto adm tair t the brake cylinder, and upon an ncrease 0% train pipe pressure to release the brakes, valve devlce interposed between the tra n line the auxiliaryreservoir .and perwas wh t a n. 1 re ur i e se after a service appl cation to auxilicry reserv ir .air to thetrain ine, and a valve G we commumcat on between the auxiliary reservoir and sai valve device.

13.. A quick-release mechanism fort air mechanism for air.

brakes oomprisin a casing formed With a train line cham er of large diameter and an auxiliary reservoir chamber below and smaller in diameter than the train line chamber, movable abutments secured across said chambers, atrain' line chamber below the abutment in the. auxiliary reservoir chamber and connected With the larger train line chamber, a train line augmentin chamber above the movable abutment of the larger train line chamber and valves operated by said movable abutment-s to control communication between the auxiliary reservoir chamber and the train line chambers and between the train line chambers and the train line augmenting chamber, and means in the train line au enting chamber normally tending to closethe valve controlling communication between the train line chamher and the train line augmenting chamber. A quick-release mechanism for air brakes comprising a casihg formed with a chamber of largecapacity an'dlwith a chambe! of considerafbl' smaller capacity below and coaxial with the larger chamber, a m' 'vabutment dividing the larger chamber i'nte a train line chamber and a train line augmenting chamber}, a' movable abutment dividing the smaller cha-mher intc} an auxiliary reservoir chamber and a train line chamber, latter chamber bein in open communication with the larger chamber, and valves q'perated by said movable ab'ut nents to control communication -betiv en the auxiliary reservoir chamber a d the train l'n and betwen the trainjlirichamhr an the train line du menting chamber s aid valves being connected to and moving with the abutment in the auxiliary reservoir chamber, the abutment subject to pressure in the train line augment ng chamber being movable lndependently 0' said valves, and a spring in th train line augmenting chamber nor ally to move the abutment and cose communicafiibn between the. train line ugmenting.

chamberanl the train Iine'chambei', 15 An air brake" apparatus co'mpri'singa train the; a brake cylinder, an auxiliary reservoi", a triple valve and a valve device actuate by train line pressure arid; auxiliarty reservoir pressure and connected to the train line and to the a'ilxiliary reservoir and operating upon an increase of train page ressureafter, a ser i e p'p catipn of t e rain line rakes to release auxiliary reservoir air suffici'en't to equalize train pipe and auxiliary reservoir res'sures. e

15, An air brake ap alratus comprising a thin line, triple Va ve, an auxiliary resl l v er'voir, a brake cylinder, a tralnlme augm'entnpiv "eservoirangl a valve device interpose tween the train line and the augmentin'g reservoir and qiperatedl' by an 11 crease in train line pressure to release air from the auxiliary reservoir to equalize the pressure therein with train line pressure.

17. An air brake apparatus comprising a train line, a brake cylinder, an auxiliary reservoir, a triple valve and a valve device actuated by train line pressure and auxiliary reservoir pressure and operating upon an increase of train line pressure after a service application of the brakes to discharge auxiliary reservoir air into the train line.

18. An air brake apparatus comprising a train line, a brake cylinder, an auxiliary reservoir, a triplevalve and a valve device operated by train line pressure and auxiliary reservoir pressure, said valve device upon a decrease of train line pressure for an application ofithe brakes being actuated by auxiliary'reservoir pressure to close communication between the auxiliary reservoir and ,train line, and upon a subsequent increase of train line pressure to open communication between the auxiliary reservoir and the train line to discharge auxiliary reservoir air into the train line.

19. A11 air brake apparatus comprising a train line, a brake cylinder, an auxiliary reservoir, a triple valve, a valve device controlling communication between the auxiliary reservoir and the train line, difierenoperated by train line pressure on the larger diaphragm to open the valve and by auxiliary reservoir pressure on the smaller diaphragm to close the valve, whereby upon a reduction of train line pressure for an application of the brakes auxiliary reservoir pressure will close said valve and upon a subsequent increase in train line pressure auxiliary reservoir, air will be discharged through said valve into the train line.

20. An air brake apparatus comprising a train line, a brake cylinder, an auxiliary reservoir, a triple valve, a valve device, 'a movable abutment therein subject to train line pressure, a second abutment in said device smaller than the first mentioned abutment and subject to train line pressure and auxiliary reservoir pressure, a valve actuated by said abutments and operating upon an increase of train line pressure after' a service application of the brakes to open communication between the auxiliary reservoir and the train line. I

21. An air brake apparatus comprising a train line, a triple valve, an auxiliary reservoir, a brake cylinder, a valve device interposed between the train line and the auxiliary reservoir and operated b variations in train line pressure to place the auxiliary reservoir in communication with the train line, and means for closing combrakes to discharge the auxiliary reservoir air into the train line, and means for closing commmunication between the auxiliary reservoir and the said valve device.

23. An air brake apparatus comprising a train line, a brake cylinder, an auxiliary reservoir, a triple valve adapted upon a reduction of train line pressure to place the train line in communication with the brake cylinder for a service application of the brakes, and a valve deviceconnected to the train line and to the auxiliary reservoir and operating upon an increase of train line pressure after a service application of the brakes to dlscharge auxiliary reservoir air under the initially charged pressure into the train line.

24. An air brake apparatus comprising'a train line, a brake cylinder, an auxiliary reservoir, 3. triple valve adapted upon a reduction of train line pressure to place the train line in communication with the brake between said augmenting reservoir and the train line said valve device operating upon a reduction of train line pressure to open a valve between the train line and the augmentin reservoir to discharge augmenting reservoir air into the train line and upon an increase of train line pressure to close said valve to. prevent recharging the augmenting reservoir through said valve, and means for permitting the slow recharging of the augmenting reservoir from the train line after the closure ofysaid. valve.

26. An air brake apparatus comprising a train line, a brake cylinder, an auxiliary res ervoir, a triple valve, a train line augmenting reservoir, a valve device interposed between said augmenting reservoir and the train line, saidvalve device operating upon a reduction of train line pressure to open a valve between the train line and the augmenting reservoir to discharge augmenting reservoir air into the train line and upon an increase of train line pressure to close said voir pressure, means operating on said abutmaaeaa valve to prevent recharging the augmenting reservoir through said valve, means constantly tending to assist train line pressure to close said valve, and means for permitting the slow recharging of the augmenting reservoir from the train line after the cl0- sure of said 'valve.

27. An air brake apparatus comprising a train line, brake cylinder, auxiliary reservoir, triple valve, a train line augmenting reservoir, a valve device interposed between the train line and the augmenting reservoir, a movable abutment therein subject to train line pressure and augmenting reservoir pressure, a valve controlled by said abutment and adapted to be closed by train line pressure and to be opened by augmenting reservoir pressure, and a restricted recharging port connecting the augmenting reservoir with the train line. i 1

28. An air brake apparatus comprising a train line; brake cylinder, auxiliary reservoir, triplevalve, a train line augmenting reservoir, a valve device interposed between the train line and the augmenting reservoir, a movable abutment therein subject to train line pressure and augmenting reservoir pressure, a valve controlled by said abutment and adapted to be closed by train line pressure and to be opened by augmenting reserment tending to assist train line pressure to close said valve, and a restricted recharging port connecting the augmenting reservoir with the train line.

29. An air brake apparatus comprising a train line, brake cylinder, auxiliary reser-' voir, triple valve, a train line augmenting reservoir, a valve device interposed between the train line and the augmenting reservoir, a movable abutment therein subject to train line pressure and augmenting reservoir pres sure, a valve controlled by said abutment and adapted to beclosed by train line pressure and to be opened by augmenting reservoir pressure, a spring acting on the aug-' menting reservoir side of the said abutment to assist train line pressure to clo se said valve, and a restricted recharging port connecting the train line with the augmenting 31. An air brake apparatus comprising a train line, a brake cylinder, an auxiliary reservoir, a triple valve, an augmenting reservoir, and a valve device actuated by train line pressure, auxiliary reservoir pressure and augmenting reservoir pressure, and operating upon a decrease of train line pressure to rapidly discharge augmenting reservoir air into the train'line and upon an increase of train line pressure after a service application of the brakes to discharge auxiliary reservoir air into the train line and to slowly recharge the augmenting reservoir.

In testimony whereof I hereunto aflix my signature in the presence of two witnesses.

SPENCER G. NEAL.

Witnesses G. V. PIERCE, G. G. Wmems. 

